Heat dissipating board structure and method of manufacturing the same

ABSTRACT

A heat dissipating board structure includes a heat dissipating board body having a first face with at least one groove; and at least one heat pipe correspondingly received in the at least one groove to flush with the first face. To manufacture the heat dissipating board structure, first provide at least one heat pipe and a heat dissipating board body; then, form at least one groove on a first face of the board body, place the heat pipe in the groove, and press the board body with a press machine to associate the heat pipe with the groove while flatten a top of the heat pipe; and finally, flush the heat pipe with the first face by removing extra material of the heat pipe that is protruded from the first face. The completed heat dissipating board structure provides upgraded heat dissipation efficiency and eliminates the problem of thermal resistance.

FIELD OF THE INVENTION

The present invention relates to a heat dissipating board structure, and more particularly to a heat dissipating board structure that provides upgraded heat dissipation efficiency and eliminates the problem of thermal resistance. The present invention also relates to a method of manufacturing a heat dissipating board structure without the problem of thermal resistance.

BACKGROUND OF THE INVENTION

The heat produced by electronic elements in various electronic devices increases with the increasing computing speed and data processing capability of the electronic devices. The heat produced by the electronic elements during the operation thereof must be timely removed, lest the heat should adversely affect the operation efficiency of the electronic devices to even cause burnout of the electronic elements thereof. According to a conventional way of removing such heat, a cooling unit is provided on a top of an electronic element. The conventional cooling unit usually includes a heat sink or a plurality of radiating fins and a cooling fan, which work cooperatively to remove the produced heat. In some cases, heat pipes are further provided to cooperate with the cooling unit, so that heat source is guided by the heat pipes to distal ends of the heat pipes and be dissipated into ambient environment. However, since an electronic device usually has only very limited internal space while the number of heat-producing electronic elements in the electronic device is large, the cooling units being correspondingly provided on the electronic elements will become very close to one another in the limited internal space of the electronic device and fail to extend their cooling ability. There is also another conventional heat dissipating way in which heat pipes are embedded in one face of a heat dissipating board to thereby form a heat dissipating element capable of overcoming the drawbacks in the conventional cooling unit and heat pipes. The conventional heat dissipating board includes at least one groove formed on one face of the board for each receiving a heat pipe therein. The heat pipe transfers the heat source to a relatively cold location on the heat dissipating board, so that the heat is dissipated into ambient air from the heat dissipating board. To facilitate easy positioning of the heat pipe in the groove, the groove is usually formed with a somewhat large allowance. Therefore, there would be a clearance left between the groove and the heat pipe positioned therein. Such clearance tends to cause thermal resistance to adversely affect the heat dissipation efficiency of the conventional heat dissipating board. Further, when the heat pipe is associated with the groove through welding, the heated surface of the heat pipe will expand to adversely affect the accuracy in assembling the heat pipe to the groove. In brief, the conventional heat dissipating board has the following disadvantages: (1) poor heat dissipation efficiency; and (2) poor assembling accuracy.

SUMMARY OF THE INVENTION

It is therefore a primary object of the present invention to provide a heat dissipating board structure that provides high performance of heat dissipation.

Another object of the present invention is to provide a method of manufacturing a heat dissipating board structure that does not have the problem of thermal resistance.

To achieve the above and other objects, the heat dissipating board structure according to the present invention includes a heat dissipating board body and at least one heat pipe. The heat dissipating board body has a first face, on which at least one groove is formed for receiving the at least one heat pipe therein. The groove has a closed side and an open side, and the heat pipe has a contact face corresponding to the closed side of the groove and flushing with the first face and an embedded face corresponding to the open side of the groove. The heat dissipating board structure of the present invention is manufactured through the following steps: providing at least one heat pipe and at least one heat dissipating board body; forming at least one groove on a first face of the heat dissipating board body; placing the heat pipe in the groove; associating the heat pipe with the groove by pressing the heat dissipating board body to flatten a top of the heat pipe to form a contact face; and removing extra material from the contact face of the heat pipe that is protruded from the first face, so that the contact face of the heat pipe is flush with the first face.

The heat dissipating board structure manufactured using the method of the present invention not only provides upgraded heat dissipation efficiency but also avoids the problem of thermal resistance. In brief, the heat dissipating board structure of the present invention has the following advantages: (1) having upgraded heat dissipation efficiency; and (2) eliminating the problem of thermal resistance.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein

FIG. 1 is an exploded perspective view of a heat dissipating board structure according to a preferred embodiment of the present invention;

FIG. 2 is an assembled view of FIG. 1;

FIG. 3 is sectioned perspective view of FIG. 2;

FIG. 3A is an enlarged view of the circled area 3A of FIG. 3;

FIG. 4 is a flowchart showing the steps included in a method of manufacturing the heat dissipating board structure according to the present invention;

FIGS. 5 to 8 are sectional views illustrating the manufacture of the heat dissipating board structure of the present invention; and

FIG. 8A is an enlarged view of the circled area 8A of FIG. 8.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer to FIGS. 1, 2 and 3 that are exploded, assembled and sectioned perspective views, respectively, of a heat dissipating board structure 1 according to a preferred embodiment of the present invention, and to FIG. 3A that is an enlarged view of the circled area 3A of FIG. 3. As shown, the heat dissipating board structure 1 includes a heat dissipating board body 11, which will also be briefly referred to as the board body throughout herein, and at least one heat pipe 12. The board body 11 has a first face 111, on which at least one groove 1111 is formed for correspondingly receiving the at least one heat pipe 12 therein. In the illustrated embodiment, seven grooves 1111 and seven heat pipes 12 are shown. Each of the grooves 1111 has an open side 1111 a and a closed side 1111 b, and each of the heat pipes 12 has a contact face 121 and an embedded face 122. The contact face 121 defines a flat face. The embedded face 122 is configured corresponding to a profile of the closed side 1111 b of the groove 1111 for fitly associating with the closed side 1111 b. The contact face 121 corresponds to the open side 1111 a of the groove 1111 and is flush with the first face 111 with the embedded face 122 of the heat pipe 12 embedded in the groove 1111. A heat-conducting bonding medium 13, such as solder paste, is applied between the embedded face 122 of the heat pipe 12 and the closed side 1111 b of the groove 1111, as can be clearly seen in FIG. 3A. With the above arrangements, the heat dissipating board structure 1 overcomes the problem of thermal resistance as found between the conventional heat dissipating board and heat pipes to thereby provide excellent heat dissipation efficiency.

The present invention also provides a method of manufacturing the above-described heat dissipating board structure 1. FIG. 4 is a flowchart showing the steps included in the method of the present invention for manufacturing the heat dissipating board structure 1; and FIGS. 5, 5A, 6, 6A, 7, 8, and 8A are sectional views illustrating the manufacture of the heat dissipating board structure 1. The heat dissipating board manufacturing steps include:

Step 21: Providing at least one heat pipe and at least one heat dissipating board body. In the step 21, at least one heat pipe 12 and a heat dissipating board body 11 is provided.

Step 22: Forming at least one groove on a first face of the heat dissipating board body. In the step 22, at least one groove 1111 is formed on a first face 111 of the board body 11 through milling or other machining process, as shown in FIG. 5. The groove 1111 so formed has an open side 1111 a and a closed side 1111 b, and has a width substantially the same as an outer diameter of the heat pipe 12. Moreover, a heat-conducting bonding medium 13, such as solder paste, can be applied in the groove 1111, as shown in FIG. 5A.

Step 23: Correspondingly placing the at least one heat pipe in the at least one groove. In the step 23, the heat pipe 12 has a contact face 121 and an embedded face 122. When placing the heat pipe 12 in the corresponding groove 1111, the embedded face 122 of the heat pipe 12 is correspondingly attached to the closed side 1111 b of the groove 1111, as shown in FIG. 5A.

Step 24: Associating the heat pipe with the groove and applying a force against the board body to flatten a top of the heat pipe. In the step 24, properly adjust the position of the heat pipe 12 in the groove 1111 of the board body 11, so that the embedded face 122 of the heat pipe 12 is stably attached to the closed side 1111 b of the groove 1111; and then, apply a force against the first face of the board body 11 having the heat pipe 12 positioned thereon by, for example, placing the heat dissipating board body 11 between a upper mold 41 and a lower mold 42 of a press machine 4 and pressing the upper mold 41 against the heat pipe 12, as shown in FIGS. 6 and 6A. Meanwhile, weld the heat pipe 12 to the heat dissipating board body 1, so that the heat pipe 12 is more firmly attached to and associated with the heat dissipating board body 11. One side of the heat pipe 12 being pressed by the upper mold 41 of the press machine 4 is flattened to form the contact face 121, which is now parallel with the first face 111 of the heat dissipating board body 11. Alternatively, the heat pipe 12 can be associated with the groove 1111 of the heat dissipating board body 11 in a manner other than welding, such as ultrasonic bonding.

Step 25: Removing extra material of the heat pipe that is protruded from the first face, so that the heat pipe is flush with the first face. In the step 25, since the contact face 121 of the heat pipe 12 is protruded from the open side 1111 a of the groove 1111 and higher than the first face 111 of the heat dissipating board 1, the contact face 121 of the heat pipe 12 is brought to flush with the first face 111 through cut operation to remove extra material at the contact face 121 of the heat pipe 12. The cut operation can be any one of milling, grinding, and planning. In the illustrated embodiment, the cut operation is completed by grinding with a sand wheel 3, as shown in FIG. 7. And, FIG. 8 is a sectional view showing the completed heat dissipating board structure 1 with an enlarged view of the circled area 8A shown in FIG. 8A.

The present invention has been described with a preferred embodiment thereof and it is understood that many changes and modifications in the described embodiment can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims. 

1. A heat dissipating board structure, comprising: a heat dissipating board body having at least one first face, on which at least one groove is formed; and the groove including a closed side and an open side; and at least one heat pipe having a contact face and an embedded face; the embedded face being correspondingly associated with the closed side of the groove, and the contact face being correspondingly located at the open side of the groove to flush with the first face of the board body, such that the heat pipe is embedded in the groove.
 2. The heat dissipating board structure as claimed in claim 1, further comprising a heat-conducting bonding medium applied between the embedded face of the heat pipe and the groove.
 3. The heat dissipating board structure as claimed in claim 2, wherein the heat-conducting bonding medium is solder paste.
 4. The heat dissipating board structure as claimed in claim 1, wherein the embedded face has a cross sectional shape the same as that of the closed side of the groove.
 5. The heat dissipating board structure as claimed in claim 1, wherein the contact face is a flat face.
 6. A method of manufacturing a heat dissipating board structure, comprising the following steps: providing at least one heat pipe and at least one heat dissipating board body; forming at least one groove on a first face of the heat dissipating board body; correspondingly placing the at least one heat pipe in the at least one groove; associating the heat pipe with the groove and applying a force against the first face of the heat dissipating board body to flatten a top of the heat pipe; and removing extra material of the heat pipe that is protruded from the first face, so that the top of the heat pipe is flush with the first face.
 7. The method of manufacturing a heat dissipating board structure as claimed in claim 6, wherein, in the associating step, the heat pipe is forced into the groove through pressing.
 8. The method of manufacturing a heat dissipating board structure as claimed in claim 6, wherein the step of removing extra material is performed by a cut operation selected from the group consisting of milling and grinding.
 9. The method of manufacturing a heat dissipating board structure as claimed in claim 6, wherein, before the step of placing the heat pipe in the groove, a heat-conducting bonding medium is first applied in the groove.
 10. The method of manufacturing a heat dissipating board structure as claimed in claim 9, wherein the heat-conducting bonding medium is solder paste.
 11. The method of manufacturing a heat dissipating board structure as claimed in claim 6, wherein, in the associating step, the heat pipe is welded to the groove.
 12. The method of manufacturing a heat dissipating board structure as claimed in claim 6, wherein, in the associating step, the heat pipe is associated with the groove through ultrasonic bonding.
 13. The method of manufacturing a heat dissipating board structure as claimed in claim 9, wherein, in the associating step, the heat pipe is welded to the groove.
 14. The method of manufacturing a heat dissipating board structure as claimed in claim 9, wherein, in the associating step, the heat pipe is associated with the groove through ultrasonic bonding. 